Thermoplastic forming tools, and assemblages thereof

Abstract

Thermoplastic forming tools and assemblages are provided for forming thermoplastic components. In particular, thermoplastic forming tools and assemblages are provided for forming thermoplastic components having precision micro-scale features and reproducible macro-scale dimensions. The thermoplastic forming assemblages can include at least a bottom tool and a top tool having a rigid tool body and an elastomer layer conformally coating at least a portion of both rigid tool bodies. The bottom and top tool can be so dimensioned that, when in the closed position, they define a cavity forming the thermoplastic component. The rigid tool bodies provide the reproducible macro-scale dimensions in the thermoplastic component, while the elastomer layers form and release the precision micro-scale features in the thermoplastic component when formed. Tool-forming structures are also provided for making thermoplastic forming tools and assemblages, as well as methods of making the thermoplastic forming tools, and methods of use for forming thermoplastic components.

We claim: 
     
       1. A thermoplastic forming assemblage for forming a thermoplastic component having precision micro-scale features and reproducible macro-scale dimensions, the thermoplastic forming assemblage comprising:
 (a) a top tool comprising: 
 a first rigid tool body having a first cavity-forming side; and 
 a first elastomer layer conformally coating at least a portion of the first cavity-forming side to create a first cavity-forming surface; and 
 (b) a bottom tool comprising: 
 a second rigid tool body have a second cavity-forming side and a second elastomer layer conformally coating at least a portion of the second cavity-forming side to create a second cavity-forming surface; 
 wherein, when in a closed position, the first cavity-forming surface and the second cavity-forming surface define a cavity for forming the thermoplastic component; 
 wherein one or both of the first cavity-forming surface and the second cavity-forming surface comprise a feature-forming surface that define the precision micro-scale features when forming the thermoplastic component; 
 wherein the first rigid tool body and the second rigid tool body are effective to provide the reproducible macro-scale dimensions in the thermoplastic component when formed; 
 wherein the first elastomer layer and the second elastomer layer are effective to form the precision micro-scale features in the thermoplastic component and to release the precision micro-scale features when formed; and 
 wherein, when in the closed position, the first elastomer layer and the second elastomer layer form a void space along a perimeter of the cavity, and wherein the thermoplastic forming assemblage comprises a cavity shutoff at an interface between the first elastomer layer and the second elastomer layer at a perimeter of the cavity when in the closed position. 
 
     
     
       2. The thermoplastic forming assemblage according to  claim 1 , wherein one or both of the first cavity-forming surface and the second cavity-forming surface comprise a recess. 
     
     
       3. The thermoplastic forming assemblage according to  claim 2 , wherein the first cavity-forming side of the first rigid tool body comprises at least one protrusion with the first elastomer layer conformally coating at least a portion of the at least one protrusion; and
 wherein the recess is configured to receive the at least one protrusion when in the closed position. 
 
     
     
       4. The thermoplastic forming assemblage according to  claim 3 , wherein the first elastomer layer comprises at least one protrusion; and
 wherein the recess is configured to receive the at least one protrusion when in the close position. 
 
     
     
       5. The thermoplastic forming assemblage according to ac claim 1 , wherein the second cavity-forming side of the second rigid tool body comprises a recess with the second elastomer layer conformally coating the recess. 
     
     
       6. The thermoplastic forming assemblage according to  claim 1 , wherein the second elastomer layer comprises a recess. 
     
     
       7. The thermoplastic forming assemblage according to  claim 1 , wherein one or both of the first elastomer layer and the second elastomer layer have a thickness ranging from about 50 micrometers to about 5 millimeters. 
     
     
       8. The thermoplastic forming assemblage according to  claim 1 , wherein one of both of a thickness variation of the first elastomer layer and a thickness variation of the second elastomer layer is about 10% or less. 
     
     
       9. The thermoplastic forming assemblage according to  claim 1 , wherein one or both of the first rigid tool body and the second rigid tool body comprises aluminum, copper, steel, plastic, ceramic, or alloys thereof. 
     
     
       10. The thermoplastic forming assemblage according to  claim 1 , wherein one or both of the first elastomer layer and the second elastomer layer comprise an elastomer selected from the group consisting of silicone rubber, fluorosilicone, fluoroelastomer (FKM), perfluoroelastomer (FFKM), ethylene acrylic elastomer, nitrile butadiene rubber (NBR), hydrogenated nitrile butadiene rubber (HNBR), ethylene propylene diene monomer (EPDM) rubber, butyl rubber, and a combination thereof. 
     
     
       11. The thermoplastic forming assemblage according to  claim 1 , wherein the thermoplastic forming assemblage comprises a cavity shutoff at an interface between the first elastomer layer and the second elastomer layer at a perimeter of the cavity when in the closed position. 
     
     
       12. The thermoplastic forming assemblage according to  claim 1 , wherein a portion of the first cavity-forming side and a portion of the second cavity forming side contact when in the closed position to form a rigid contact limiting a degree of compression of the bottom tool and the top tool. 
     
     
       13. The thermoplastic forming assemblage according to  claim 1 , wherein the cavity shutoff forms a side of the void space located between the void space and the cavity. 
     
     
       14. The thermoplastic forming assemblage according to  claim 1 , wherein one or both of the cavity shutoff and the void space extend around an entire perimeter of the cavity. 
     
     
       15. The thermoplastic forming assemblage according to  claim 14 , wherein, when in the closed position, the first elastomer layer and the second elastomer layer contact at an interface substantially perpendicular to both the first cavity-forming side and the second cavity forming side to form a gasket sealing the void space. 
     
     
       16. The thermoplastic forming assemblage according to  claim 1 , wherein, when in the closed position, the first elastomer layer and a second elastomer layer contact at an interface substantially perpendicular to both the first cavity-forming side and the second cavity forming side to form a gasket sealing the void space. 
     
     
       17. The thermoplastic forming assemblage according to  claim 16 , further comprising a heating element for one or both of the first rigid tool body and the second rigid tool body. 
     
     
       18. The thermoplastic forming assemblage according to  1 , further comprising a heating element for one or both of the first rigid tool body and the second rigid tool body. 
     
     
       19. The thermoplastic forming assemblage according to  claim 1 , further comprising a cooling element for one or both of the first rigid tool body and the second rigid tool body. 
     
     
       20. The thermoplastic forming assemblage according to  claim 1 , wherein the thermoplastic forming assemblage comprises a mold for hot embossing the thermoplastic component or a mold for injection molding the thermoplastic component. 
     
     
       21. The thermoplastic forming assemblage according to  claim 1 , wherein the precision micro-scale features have a negative draft angle. 
     
     
       22. The thermoplastic forming assemblage according to  claim 1 , wherein the bottom tool comprises a plurality of recesses,
 wherein each recess in the plurality of recesses is coated with an elastomer layer conformally coating the recess so as to create a plurality of second cavity forming surfaces. 
 
     
     
       23. The thermoplastic forming assemblage according to  claim 22 , wherein the top tool comprises a plurality of protrusions,
 wherein each protrusion in the plurality of protrusions is coated with an elastomer layer conformally coating the protrusion to form a plurality of the first cavity forming surfaces; and 
 wherein the plurality of first cavity forming surfaces and the plurality of second cavity forming surfaces, when in the closed position, form a cavity for forming a plurality of thermoplastic components. 
 
     
     
       24. The thermoplastic forming assemblage according to  claim 22 , wherein the thermoplastic forming assemblage comprises a plurality of top tools;
 wherein each of the top tools comprise a protrusion coated with an elastomer layer conformally coating the protrusion to form a first cavity forming surface on each of the top tools in the plurality of top tools; and 
 wherein the plurality of first cavity forming surfaces and the plurality of second cavity forming surfaces, when in the closed position, form a cavity for forming a plurality of thermoplastic components.